# HTML Service Admin UI - v0.1.5

## Overview

Version 0.1.5 represents a **major architectural fix** that resolves critical bugs in the v0.1.4 playground and establishes a robust **Web Component architecture** for proper component initialization and API integration.

## What's New in v0.1.5

### 🔧 Major Fixes

1. **Web Component Architecture** (Fixed Constructor Issue)
   - Converted to proper `HTMLElement` subclass
   - Fixed constructor execution that was failing in v0.1.4
   - Proper component lifecycle with `connectedCallback`
   - Component auto-initializes when mounted to DOM

2. **Complete API Integration Overhaul**
   - Fixed endpoint configuration access pattern
   - Corrected URL construction (removed double prefix)
   - Fixed payload data extraction
   - Switched to combined `/html/to/dict/hashes` endpoint
   - Proper HTML text response handling

3. **3-Column Layout Refinement**
   - Original HTML input
   - Layout & Content Objects (dual view: Dict + Hashes)
   - Created HTML output
   - Clean, professional UI

4. **Full Workflow Implementation**
   - Load sample → Parse → Rebuild pipeline works end-to-end
   - Auto-execution on page load (micro sample)
   - Debug panel for testing individual steps
   - Complete round-trip HTML transformation

### 📋 Complete Fix Summary

**7 Critical Issues Resolved**:
1. ✅ **Web Component Architecture** - Proper HTMLElement inheritance
2. ✅ **Endpoint Configuration** - Correct access to v0.1.3 config
3. ✅ **URL Construction** - Fixed 404 errors (removed `/html-service/v0` prefix)
4. ✅ **Payload Extraction** - Extract data, not metadata wrappers
5. ✅ **Combined Endpoint** - Use `/html/to/dict/hashes` for compatibility
6. ✅ **Response Handling** - Use `response.text()` for HTML output
7. ✅ **Complete Integration** - Full pipeline works flawlessly

## Features

✅ **Web Component Based** - Modern, standards-compliant architecture  
✅ **Auto-Initialization** - Component initializes automatically on mount  
✅ **Complete API Integration** - All endpoints working correctly  
✅ **Full Transformation Pipeline** - HTML → Parse → Rebuild → HTML  
✅ **Dual View Middle Column** - Structure (Dict) + Content (Hashes)  
✅ **Debug Panel** - Quick testing of individual steps  
✅ **Syntax Highlighting** - Reuses v0.1.4 highlighter  
✅ **Copy/Download** - Export transformation results  
✅ **Responsive Design** - Works on desktop, tablet, mobile  
✅ **Zero External Dependencies** - 100% native web platform  

## Project Structure

```
v0.1.5/
├── index.html                           # Dashboard (reuses v0.1.1)
├── playground.html                      # Playground page
├── README.md                            # This file
├── CHANGELOG.md                         # Detailed fix documentation
├── css/
│   └── playground.css                   # 3-column layout styles
├── components/
│   └── playground-controller/           # NEW: Web Component controller
│       └── playground-controller.js     # Main controller logic
├── data/
│   └── samples.js                       # Sample HTML files (micro, simple, complex)
```

### Reused from Previous Versions

**From v0.1.3**:
- `js/config/Endpoints__Config.js` - Endpoint configuration

**From v0.1.4**:
- `js/utils/Syntax__Highlighter.js` - JSON/HTML syntax highlighting

**From v0.1.1**:
- `components/top-nav/` - Navigation component
- `css/common.css` - Shared styles

## Usage Guide

### Quick Start

1. **Open Playground**: Navigate to `playground.html`

2. **Auto-Execution**: Page automatically runs full workflow on load:
   - Loads micro sample HTML
   - Parses to Dict + Hashes
   - Rebuilds HTML
   - Displays all results

3. **Manual Testing**: Use debug panel (bottom-right) for step-by-step testing

### Transformation Playground

#### Load Sample
```
Select from dropdown:
├── Micro HTML (Minimal) - Tiny test case
├── Simple HTML - Basic document
├── Complex HTML (Deep Nesting) - Advanced structure
└── Custom (Paste Your Own) - Manual input
```

#### Parse HTML
```
Click "▶ Parse" in middle column
→ Calls: POST /html/to/dict/hashes
→ Returns: Dict structure + Hash mapping
→ Displays: Both in dual view
```

#### Rebuild HTML
```
Click "▶ Rebuild" in right column
→ Calls: POST /hashes/to/html
→ Returns: Reconstructed HTML
→ Displays: With syntax highlighting
```

#### Export Results
```
Copy button → Clipboard
Download button → Save as .html file
```

### Debug Panel

Quick testing controls (bottom-right corner):

- **📄 Load Micro Sample** - Load minimal HTML
- **📁 Load Simple Sample** - Load basic document
- **▶️ Parse HTML** - Execute parse transformation
- **🔄 Rebuild HTML** - Execute rebuild transformation
- **⚡ Full Flow** - Run complete pipeline

## Component Architecture

### Web Component Pattern

```javascript
// playground-controller.js
class PlaygroundController extends HTMLElement {
    constructor() {
        super();
        // Initialize state
    }
    
    connectedCallback() {
        // Component mounted to DOM
        // Get DOM references
        // Attach event listeners
        // Auto-run initial flow
    }
}

// Register component
customElements.define('playground-controller', PlaygroundController);
```

### Component Lifecycle

1. **Constructor** - Initialize state variables
2. **Connected** - Component added to DOM
3. **Get References** - Query DOM elements
4. **Attach Listeners** - Wire up event handlers
5. **Auto-Execute** - Run initial transformation
6. **Disconnected** - Cleanup (if needed)

### Key Methods

```javascript
// Core transformations
async parseHtml()      // HTML → Dict + Hashes
async rebuildHtml()    // Dict + Hashes → HTML

// Sample management
loadSample(name)       // Load pre-defined HTML
clearInput()           // Reset input

// Output management
copyOutput()           // Copy to clipboard
downloadOutput()       // Download as file

// UI feedback
showStatus(type, msg)  // Display status message
updateCharCount()      // Update character counter
```

## API Integration

### Parse Endpoint

**Combined endpoint returns both dict and hashes**:

```javascript
POST /html/to/dict/hashes
Content-Type: application/json

{
  "html": "<html><body>Text</body></html>",
  "max_depth": 256
}

Response:
{
  "html_dict": {
    "tag": "html",
    "attrs": {},
    "nodes": [
      {
        "tag": "body",
        "nodes": [
          {
            "type": "TEXT",
            "data": "098890dde0"  // Hash ID
          }
        ]
      }
    ]
  },
  "hash_mapping": {
    "098890dde0": "Text"  // Simple string mapping
  },
  "node_count": 3,
  "max_depth": 2,
  "total_text_hashes": 1,
  "max_depth_reached": false
}
```

### Rebuild Endpoint

**Returns HTML text (not JSON)**:

```javascript
POST /hashes/to/html
Content-Type: application/json

{
  "html_dict": {
    "tag": "html",
    "nodes": [{ "type": "TEXT", "data": "098890dde0" }]
  },
  "hash_mapping": {
    "098890dde0": "Text"
  }
}

Response: (text/html)
<!DOCTYPE html>
<html>Text</html>
```

## Sample Files

### micro
Minimal HTML for quick testing:
```html
<html>
    <head>
        <title>an title</title>
    </head>
    <body>
        <p>A paragraph with <b>a bold</b> item</p>
    </body>
</html>
```

### simple
Basic HTML document with common elements (lists, headings, paragraphs).

### complex
Deeply nested structure with tables, nested lists, and multiple sections.

## Technical Implementation

### Web Component Registration

```javascript
// Component auto-registers on import
import './components/playground-controller/playground-controller.js';

// HTML usage
<playground-controller></playground-controller>
```

### Endpoint Access Pattern

```javascript
// v0.1.3 config structure
const Endpoints__Config = {
    'html-to-dict': {
        route: '/html/to/dict',
        method: 'POST',
        // ...
    }
}

// Correct access (v0.1.5)
const endpoint = Endpoints__Config['html-to-dict'];
const url = endpoint.route;  // Use directly, no prefix
```

### Response Handling

```javascript
// JSON response (parse)
const result = await response.json();
this.currentDict = result.html_dict;

// Text response (rebuild)
const htmlResult = await response.text();
this.currentCreatedHtml = htmlResult;
```

## IFD Principles Applied

✅ **Version Independence** - Completely self-contained  
✅ **Copy Forward** - Built by fixing v0.1.4 issues  
✅ **Real Integration** - Calls actual API endpoints  
✅ **Progressive Enhancement** - Each fix builds on previous  
✅ **Comprehensive Documentation** - 8+ detailed fix documents  
✅ **Zero Dependencies** - Pure native web platform  
✅ **Path Independence** - All imports use full version paths  

## Differences from v0.1.4

### New Architecture
- **Web Component** - Proper `HTMLElement` subclass (not plain class)
- **Auto-Initialization** - Component initializes on mount
- **Event Lifecycle** - Proper `connectedCallback` implementation

### Fixed Issues
- **Constructor Execution** - Now runs correctly
- **API Integration** - All 7 critical issues resolved
- **Endpoint Access** - Correct v0.1.3 config usage
- **URL Construction** - No double prefix
- **Data Extraction** - Proper payload handling
- **Response Types** - JSON vs. Text handled correctly

### Enhanced Features
- **Debug Panel** - Quick testing controls
- **Auto-Execution** - Runs full flow on load
- **Status Messages** - Better user feedback
- **Error Handling** - Comprehensive try-catch blocks

### File Reorganization
- `js/playground.js` → `components/playground-controller/playground-controller.js`
- `js/samples.js` → `data/samples.js`

## Development Notes

### Debugging

**Console Logs**: Component provides detailed logging:
```
🎮 PlaygroundController constructor called
🎮 PlaygroundController connectedCallback - component mounted!
✅ DOM references obtained
✅ Event listeners attached
🚀 Running auto-flow: Load Micro → Parse → Rebuild
📄 Loading sample: micro
✅ Sample loaded: 143 characters
🔍 Parse requested...
📤 Sending 143 characters to API...
🌐 Calling combined dict/hashes endpoint...
   Response status: 200
📥 API response received
✅ Parse complete!
🔧 Rebuild requested...
📤 Sending Dict + Hashes to API...
🌐 Calling reconstruction endpoint...
   Response status: 200
📥 Rebuild response received (HTML)
✅ Rebuild complete!
✅ Full flow complete!
```

### Network Inspection

**Expected API Calls**:
1. `POST /html/to/dict/hashes` → 200 OK (JSON response)
2. `POST /hashes/to/html` → 200 OK (HTML text response)

### Common Issues

**Problem**: Component not initializing  
**Solution**: Check browser console for `customElements.define` errors

**Problem**: 404 errors on API calls  
**Solution**: Verify `/html/to/dict/hashes` endpoint exists

**Problem**: JSON parse error  
**Solution**: Ensure using `response.text()` for rebuild endpoint

## Testing

### Manual Testing

1. Open `playground.html`
2. Observe auto-execution in console
3. Check all three columns populate correctly
4. Try each debug button individually
5. Test copy/download functionality


## Version History

- **v0.1.5** (Current) - Web Component architecture + Complete API integration fix
- **v0.1.4** - Syntax highlighting + UI improvements (had initialization bug)
- **v0.1.3** - Endpoint configuration + JSON config
- **v0.1.2** - ES6 modules + Refactoring
- **v0.1.1** - Transformation playground + Web components
- **v0.1.0** - Initial dashboard + Basic API integration

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